The existing displayers are mostly based on amorphous silicon (a-Si), i.e. the thin film transistors (TFT) on the display panels are mostly made of amorphous silicon semiconductor materials. But in comparison, polysilicon (Poly-Si) has a higher electron mobility and has been deemed as a better TFT manufacturing method than amorphous silicon.
The current method of preparing a polysilicon TFT normally comprises: firstly preparing an amorphous silicon layer; transferring the amorphous silicon layer into a polysilicon layer using an excimer laser annealing (ELA) method; and finally forming the thin film transistor according to conventional workflow. The inventor finds at least the following problems in the current method: more defects (e.g. grain boundary defect, grain non-uniformity) in the process of forming the polysilicon, poor uniformity of the resultant polysilicon layer, and thus poor electric performance and reliability of the polysilicon thin film transistor.